论文部分内容阅读
目的快速检出耐甲氧西林凝固酶阴性葡萄球菌。方法利用聚合酶链反应（ＰＣＲ）检测耐甲氧西林凝固酶阴性葡萄球菌，建立一种从葡萄球菌中快速提取ＤＮＡ方法，用粗提物为模板，检测编码耐甲氧西林葡萄球菌青霉素结合蛋白的ｍｅｃＡ基因，扩增产物为５３３ｂｐ大小。结果药敏法鉴定为耐甲氧西林凝固酶阴性葡萄球菌２１株，１００％ｍｅｃＡ基因阳性，２３株对甲氧西林敏感的凝固酶阴性葡萄球菌中有９株用ＰＣＲ扩增出ｍｅｃＡ基因片段。利用ｒ－３２Ｐ标记寡核苷酸作为探针，Ｓｏｕｔｈ－ｅｒｎ杂交结果与ＰＣＲ检测结果完全一致，证实５３３ｂｐ片段为耐甲氧西林凝固酶阴性葡萄球菌ｍｅｃＡ基因特异性片段。结论ＰＣＲ方法具有快速、敏感的优点，并能特异地检出临界（ＭＩＣ＝０．５～２ｍｇ／Ｌ）耐甲氧西林凝固酶阴性葡萄球菌株。
Objective Rapid detection of methicillin-resistant coagulase-negative staphylococci. Methods Polymerase chain reaction (PCR) was used to detect methicillin-resistant coagulase-negative staphylococci. A rapid DNA extraction from staphylococcus was established. The crude extracts were used as template to detect methicillin-resistant staphylococcal penicillin-binding protein Of the mecA gene, amplified product was 533bp size. Results The results showed that 21 strains of methicillin-resistant coagulase-negative staphylococci were methicillin-resistant, with 100% mecA gene positive and 9 of 23 strains of methicillin-sensitive coagulase-negative staphylococci. The mecA gene fragment was amplified by PCR. Using r-32P labeled oligonucleotide as a probe, South-ern hybridization results were in good agreement with PCR results, confirming that the 533 bp fragment was a specific fragment of methicillin-resistant coagulase-negative staphylococcal mecA gene. Conclusion PCR method has the advantages of fast and sensitive, and can detect the methicillin-resistant coagulase-negative Staphylococcus aureus strains (MIC = 0.5-2mg / L) specifically.